Manufacturer: Honeywell
Product No.: 621-9939C
Country of origin:United States
Product Type: PLC Communication Modules
Payment: T/T, Western Union
Weight: 2000g
Dimensions: 260 x 160 x 50 mm
Shipping port: Xiamen
Warranty: 12 months
Designed to facilitate reliable point-to-point and multi-drop communication, the Honeywell 621-9939C establishes high-speed serial links within industrial automation topologies. As a dedicated communications interface for the Honeywell IPC 620 PLC platform, this module bridges the control processor with external serial peripherals, operator terminals, or upstream host computers. By offloading serial protocol processing from the main CPU, it ensures deterministic cycle times and robust field network performance in demanding manufacturing environments.
| Parameter | Specification |
|---|---|
| Manufacturer | Honeywell |
| Model Number | 621-9939C |
| Series | IPC 620 / 621 Series |
| Module Type | Serial Link Module (I/O Interface) |
| Interface Standard | Serial RS-232 / RS-422 / RS-485 (Hardware Selectable) |
| Operating Temperature | 0 to 60 degC |
| Storage Temperature | -40 to 85 degC |
| Relative Humidity | 5% to 95% Non-condensing |
| Country of Origin | USA |
| Shipping Weight (Calculated) | 2.0 kg (4.4 lbs) |
| Package Dimensions (Calculated) | 260 x 160 x 50 mm |
The 621-9939C is a direct physical and functional replacement for previous revisions of the 621 serial link module architecture. Ensure that your processor's firmware supports multi-drop communications protocol maps if deploying this module in multi-node configurations. It maintains hardware backplane compatibility with all standard IPC 620 rack slots.
To prevent data corruption on long-distance serial networks, verify that proper termination resistors are installed on RS-485 drop points. Avoid routing the communication cable tray parallel to high-power motor lines or variable frequency drive (VFD) outputs to prevent electromagnetic interference from interrupting the link.
Before inserting the module into the rack chassis, configure the onboard DIP switches to match the desired baud rate, parity, and node address of your controller software program. Standardize on shielded, twisted-pair cabling and ground the shield at a single reference point to optimize signal integrity.
Disconnect all primary AC and DC power supplies feeding the system chassis before inserting or removing the module. Failure to de-energize the rack could result in electrical shock, backplane arc-flashing, or permanent hardware failure.
Power down the Honeywell IPC 620 chassis entirely.
Configure the module DIP switches for addressing, parity, and communication speed based on the design schematic.
Align the module card edge with the plastic guides in the designated chassis slot.
Gently slide the module in until it seats firmly into the backplane connector; tighten the retaining screws to secure the unit.
Attach the external serial communication cabling to the front connector, apply system power, and monitor diagnostic LEDs.
Global Express Shipping
Returns & Warranty
Global Express Shipping
Returns & Warranty
Orders are processed and delivered Monday-Friday (excluding public holidays).
For full eligibility, restocking fees, and international return details, please view our official Refund & Return Policy .
| Country of origin |
United States
|
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